Category Archives: Plants & Fungi

plants & fungi

Jack O’Lanterns Glow Green in the Dark

Jack O’Lantern mushroom at night, Randolph County, WV (photo from Wikimedia Commons)

30 October 2023

If you’ve only seen Jack O’Lantern mushrooms (Omphalotus olearius) during the day you may have thought they were named for their orange pumpkin-like color.

Jack O’Lantern mushrooms, Schenley Park, 30 Sept 2018 (photo by Kate St. John)

Instead they are aptly named because they glow green in the dark, as shown in the top photo.

Perhaps, like Armillaria mushrooms, Omphalotus olearius is bioluminescent because of the chemical reaction they use to consume decaying wood. Armillaria‘s chemical reaction glow is described in this vintage article on foxfire.

Jack O’Lantern is one of only about 112 species of fungi that are bioluminescent. Find out more at 10 Bioluminescent Mushrooms That Glow in the Dark.

p.s. Never eat Jack O’Lantern (Omphalotus olearius). It is poisonous!

(photos from Wikimedia Commons & Kate St. John; click on the Wiki caption to see the original)

Seen in Late September

Honeybee on asters, Schenley Park, 28 Sept 2023 (photo by Kate St. John)

7 October 2023

The best photos from this week have been published already (Yesterday at Hays Woods Bird Banding) so I’m reaching back to late September for a few of things I’ve seen.

Bees of all kinds are attracted to deep purple asters beside the Westinghouse Memorial pond in Schenley Park. The honeybee, above, is hard to see near the flower’s orange center.

At Duck Hollow, yellow jewelweed still has flowers as well as fat seed pods. Try to pull one of the pods from the stem and see what happens.

Yellow jewelweed flower and seeds, Duck Hollow, 26 Sept 2023 (photo by Kate St. John)

On 28 September I explored the slag heap flats near Swisshelm Park where (I think) solar arrays will be installed. Because the slag is porous the flats are a dry grass/scrub land where this shrub would have done well except that it’s been over-browsed by too many deer. It looks like bonsai.

Deer damage at the future site of solar flats, NMR Valley, 28 Sept 2023 (photo by Kate St. John)

Deer overpopulation is also evident by the browse line at the edge of the flats.

Browse line at the edge of the future solar flats,NMR Valley, 28 Sept 2023 (photo by Kate St. John)

On 26 September at Duck Hollow I encountered an optical illusion where Nine Mile Run empties into the Monongahela River. It looks as if this downed, waterlogged tree is damming the creek and that the water is lower on the downriver side of it. This illusion seems to be caused by the smooth water surface on one side of the log.

Optical illusion: the log is damming Nine Mile Run, 26 Sept 2023 (photo by Kate St. John)

We found a tiny red centipede crossing the trail at Frick Park on 30 September …

Tiny red centipede, Frick Park, 30 Sept 2023 (photo by Kate St. John)

… and a puffball mushroom outside the Dog Park.

Puffball mushroom, Frick Park, 30 Sept 2023 (photo by Kate St. John)

On 27 September hundreds, if not thousands, of crows gathered at dusk near Neville Street in Shadyside before flying to the roost. I thought this would happen again the next day but they changed their plan and have not come this close again.

Hundreds of crows take off from a roof on Neville Street, 27 Sept 2023 (photo by Kate St. John)

Sometimes sunrise is the most beautiful part of the day.

Sunrise at Neville Street, 28 Sept 2023 (photo by Kate St. John)

These photos don’t give the impression that it’s been abnormally dry, but precipitation in Pittsburgh is down 6″ for the year. Almost 2″ of that deficit occurred in September. The Fall Color Prediction says our leaf color-change is later than usual.

(photos by Kate St. John)

Invasive Look-Alike of Devil’s Walking Stick

Tennessee warbler on Aralia sp., 6 Sept 2023 (photo by Dave Brooke)

2 October 2023

In September birders lurk near devil’s walking stick in Frick Park because the plants attract birds on migration. Crawling with tiny insects and full of fruit, devil’s walking stick is often swarmed with visiting warblers, cedar waxwings and robins. But is it really devil’s walking stick (Aralia spinosa)? Or is it the invasive look-alike Japanese angelica (Aralia elata)? Or even worse, is it a hybrid?

I didn’t know about this possibility until Dave Brooke posted photos of two warblers on devil’s walking stick. The first was a Tennessee warbler, at top, followed by a Cape May warbler, below, that landed on the same perch in the same pose just 25 seconds later.

Cape May warbler on Aralia sp., 6 Sept 2023 (photo by Dave Brooke)

Anne Swaim responded to Dave’s post saying “Probably Aralia elata, the Japanese Angelica. Great bird attractant (but really invasive.) Same genus as the native Devil’s walking stick.”

Native to eastern Russia, China, Korea and Japan, Japanese angelica (Aralia elata) was brought to the U.S. as an ornamental plant. It’s well known in eastern Pennsylvania and New York state because those areas are outside Aralia spinosa‘s native range. Pittsburgh is on the border though, so I always assumed I was looking at the native plant.

Aralia spinosa‘s native range (map from Wikimedia Commons)

It’s so hard to tell them apart that New York Botanical Garden posted this guide to invasive look-alikes. Here’s a screenshot from the Aralia sp pages:

screenshot from Mistaken Identity? Invasive Plants and Their Native Look-Alikes, A Guide for the Mid-Atlantic (posted by NY Botanical Garden)

Their Quick ID is helpful for non-botanists like me.

Quick ID of Aralia elata (invasive alien):

  1. Leaf veins: Main lateral veins running all the way to the tips of teeth at the leaf margin.
  2. Inflorescence: Inflorescence shorter, typically 30–60 cm long, and WITHOUT a distinct central axis (often wider than long, with base usually surrounded by and even overtopped by foliage).

Quick ID of Aralia spinosa (native):

  1. Leaf veins: Main lateral veins branching and diminishing in size before reaching the leaf margin (smaller branching veins may run to the tips of teeth)
  2. Inflorescence: Inflorescence longer, often 1–1.2 m long, WITH a distinct central axis (typically longer than wide, base usually elevated above foliage).
Mistaken Identity? Invasive Plants and Their Native Look-Alikes, A Guide for the Mid-Atlantic (posted by NY Botanical Garden)

I tried to identify the plants at Frick by looking at the leaves but it’s very hard to do. The easiest way is by looking at the inflorescence — the tower of flowers.

Japanese angelica’s (Aralia elata) inflorescence basically lies flat. It does not have a central stem and the leaves may cover some of the flowers. Here’s Japanese angelica at Frick.

Inflorescence below the leaves = Japanese elata in Frick Park (photo by Kate St. John)

Devil’s walking stick’s (Aralia spinosa) inflorescence stands tall above the leaves on a central stalk.

Inflorescence above the leaves on a central stalk = Devil’s walking stick (photo by Tom Potterfield via Flickr Creative Commons license)

Now I’ve started looking at all the Aralias and asking: Which one are you?

You might know of a stand of a devil’s walking stick you’d like to examine too. To figure out its identity download the Mistaken Identity guide at ==>

Also see Tom Potterfield’s Flickr album with photos of both species.

Meanwhile, for the sake of the warblers I am deciding not to get excited that these plants are alien. The birds love them so much and I love the birds so …

p.s. Read more about Japanese angelica’s invasive qualities at the Brandywine Conservancy: Invasive Species Spotlight: Japanese Angelica Tree (Aralia elata). Here’s where it occurs in the U.S. Yes, in Allegheny County. Wonder who planted it.

Japanese angelica in the U.S. (map from Invasive Plant Atlas, EDD)

(photos by Dave Brooke,, Kate St. John and Tom Potterfield. Click the links in the captions to see the originals)

Loves Disturbed Soil

Pilewort seeds blow away in the wind, 20 Sep 2023 (photo by Kate St. John)

25 September 2023

Have you seen white fluff blowing in the wind lately? The fluff is not from dandelions. At this time of year it’s from pilewort.

Pilewort (Erechtites hieraciifolius) is a native plant in the Aster family that looks very weedy, even ugly. At two to eight feet tall the flower heads on the tips of the branches look like seed pods because they barely open to expose pistils and stamens. To appreciate the flower you need a magnifying glass. Its beauty is microscopic.

It doesn’t take much wind to set it going. Do you see the flying fluff in this closeup? Look for the tiny yellow arrow in this photo and the one at top.

Pilewort near Phipps’ parking lot, 20 Sep 2023 (photo by Kate St. John)

Why is it called pilewort? The common name literally means “hemorrhoid plant.” Penn State Extension explains.

Native Americans used American burnweed [pilewort] to treat rashes caused by exposure to poison ivy and poison sumac. Medicinally, it has also been used as an emetic and to treat dysentery, eczema, diarrhea, and hemorrhoids. It has been used to create a blue dye for wool and cotton and, despite its intense flavor, can be eaten raw or cooked.

Penn State Extension: American burnweed

Pileweed’s other common name is American burnweed because it grows easily after brush fires. It loves disturbed soil and is easy to find by the side of the road, in churned up gardens, and in urban areas. In this age of bulldozers, roto-tillers and garden digging, pilewort has many opportunities to germinate.

I found a lot of it at Duck Hollow.

Pilewort at Duck Hollow, 18 Sep 2023 (photo by Kate St. John)
Pilewort at Duck Hollow, 18 Sep 2023 (photo by Kate St. John)

Perhaps it’s a good thing that pilewort grows prolifically. A 2002 study in Japan found that Erechtites hieraciifolius is good at absorbing the greenhouse gas, nitrogen dioxide, turning it into an organic form.

It may not be beautiful but pilewort plants itself by the side of the road and then cleans the air.

(photos by Kate St. John)

What is a -Wort?

Purple milkwort, Sewickley Heights Park, 8 Sept 2023 (photo by Kate St. John)

12 September 2023

Why do some plants have the suffix “-wort” in their names?

The suffix “-wort” simply means “plant.” In earlier centuries, plant common names often referred to physical characteristics, resemblance, or recommended medicinal uses.

Univ of Wisconsin-Madison Arboretum: Gardening with Native Plants: Worts and Weeds, pt. 1

Here are some recently blooming “-worts.”

Purple milkwort (Polygala sanguinea), above, is native to North America. “The genus name Polygala comes from the ancient Greek “much milk”, as the plant was thought to increase milk yields in cattle.” I have no idea if this works.

Mugwort (Artemisia vulgaris), related to ragweed, is used in cooking and has been used medicinally. It has a bitter flavor. Why “mug”? I don’t know.

Mugwort leaves are white underneath (photo by Kate St. John)
Mugwort leaves are white underneath (photo by Kate St. John)
Mugwort flowers are brown in September, Schenley Park, 23 Sept 2021 (photo by Kate St. John)

Pilewort (Erechtites hieraciifolius) is a member of the Aster family that grows easily in disturbed soil. Quirky Science says the “reported uses include the treating of hemorrhage, dysentery, skin diseases, and cholera. It is a purgative and emetic. The name suggests it is good in treating piles (hemorrhoids).”

Pilewort, Pittsburgh East End, 28 Aug 2023 (photo by Kate St. John)
Pilewort flower heads and seeds (photo by Kate St. John)
Pilewort flower heads and seeds, Sept 2016 (photo by Kate St. John)

St. Johns wort (Hypericum perforatum), imported from Europe, is so-named because it blooms in June and was traditionally harvested on St. John’s Day, June 24, to adorn homes and ward off evil. It is an herbal treatment for depression and has been planted nearly worldwide.

St. Johns wort, South Side of Pittsburgh, July 2022 (photo by Kate St. John)

(photos by Kate St. John)

Seen This Week

Turtleheads blooming in Schenley Park, 3 Sept 2023 (photo by Kate St. John)

9 September 2023

Seen this week:

Turtleheads and late boneset flowers at Schenley Park. Do you see the honeybee?

Honeybee flies to late boneset, Schenley Park, 4 Sept 2023 (photo by Kate St. John)

A rainbow with crows over Oakland.

Rainbow over Shadyside on 7 Sept 2023 (photo by Kate St. John)

Fiery sunset on 7 September.

Fiery sunset on 7 Sept 2023 (photo by Kate St. John)

Six deer in Schenley Park — only 5 made it into the photo.

Five of six does in Schenley Park along the Bridle Trail, 4 Sept 2023 (photo by Kate St. John)

But there’s a photo of deer I wish I’d been able to take: Friday morning 8 September along 5th Ave between the Cathedral of Learning and Clapp Hall I saw 3 deer — 2 does and 1 fawn — standing on the pavement at Clapp Hall. They were close to the curb of 5th Ave at Tennyson as they tried to figure out how to cross 5th Ave during rush hour.

(photos by Kate St. John)

p.s. Right now there are 2 flamingos in PA in Franklin County east of Chambersburg.

Invasive Beefsteak

Beefsteak plant, Lancaster County, September 2022 (photo by Kate St. John)

Here’s a pretty plant, an invasive alien, that I’ve not seen in Pittsburgh but is easy to find in Lancaster County, PA where I took this picture.

Beefsteak plant (Perilla frutescens) is a member of the mint family native to Southeast Asia and the Indian highlands and is grown as a crop for Japanese, Korean and Chinese cuisine. Its common names include shiso and Korean perilla. The “beefsteak” name was coined because the darkest varieties have leaves as red as meat. The wild plants I saw in Lancaster County had green leaves and dark red stems.

Perilla frutescens is widely cultivated in Asia as an edible plant but it has downsides including contact dermatitis from touching the leaves and anaphylaxis after consuming a large amount of seeds. Those who cultivate it know what to do but the rest of us should be cautious.

Brought to the U.S. as an ornamental beefsteak plant escaped to the wild and is now invasive in six states from Pennsylvania to Tennessee. The plant is always toxic to cattle, horses and other ruminants including white-tailed deer.

States listing Perilla frutescens as invasive (map from

Since deer don’t eat it, it may have been touted as a “deer resistant” plant at the nursery but don’t buy it! This plant spreads way too easily.

(credits are in the captions with links where applicable)

Yesterday at Schenley Park on 8/27

Schenley Park outing, 27 August 2023 (photo by Kate St. John)

28 August 2023

Yesterday turned into a nice day, but when eight of us met at Schenley Park at 8:30am the temperature was cool with low clouds and the sky was blank gray. Normally the birds would have slept in but the migrants were hungry. We found 22 species.

Best Bird is hard to choose. Was it the belted kingfisher that hunted over Panther Hollow Lake? The ruby-throated hummingbirds that floated among the trees? Or the warblers — Blackburnian, magnolia and chestnut-sided?

Between birds the bugs took center stage. Milkweed bugs swarmed on swamp milkweed pods …

Milkweed bugs on swamp milkweed seed pods, Schenley, 27 August 2023 (photo by Kate St. John)

… and spotted lanternflies sipped on the Ailanthus trees that inspired my blog about sooty mold on honeydew. I was curious: Did the rain wash away the sooty mold? No.

Spotted lanternfly honeydew below an Ailanthus tree is black with sooty mold, Schenley Park, 27 Aug 2023 (photo by Kate St. John)

Fourteen Canada geese flew over to join the 70 already grazing on Flagstaff Hill. Geese were absent from Flagstaff Hill this summer while they molted their wings feathers and did not return in large numbers until early August.

Here’s our eBird checklist: Schenley Park, Allegheny, Pennsylvania, Aug 27, 2022 8:30A – 10:30A

Canada Goose (Branta canadensis) 14
Rock Pigeon (Feral Pigeon) (Columba livia (Feral Pigeon)) 2
Mourning Dove (Zenaida macroura) 9
Ruby-throated Hummingbird (Archilochus colubris) 2
Belted Kingfisher (Megaceryle alcyon) 1
Red-bellied Woodpecker (Melanerpes carolinus) 2
Downy Woodpecker (Dryobates pubescens) 5
Northern Flicker (Colaptes auratus) 2
Blue Jay (Cyanocitta cristata) 5
Carolina Chickadee (Poecile carolinensis) 8
Tufted Titmouse (Baeolophus bicolor) 7
White-breasted Nuthatch (Sitta carolinensis) 2
Carolina Wren (Thryothorus ludovicianus) 3
Gray Catbird (Dumetella carolinensis) 1
American Robin (Turdus migratorius) 4
House Finch (Haemorhous mexicanus) 3
Chipping Sparrow (Spizella passerina) 15
Song Sparrow (Melospiza melodia) 1
Magnolia Warbler (Setophaga magnolia) 3
Blackburnian Warbler (Setophaga fusca) 2
Chestnut-sided Warbler (Setophaga pensylvanica) 2
Northern Cardinal (Cardinalis cardinalis) 6

The next outing will be 24 September at 8:30a in Schenley Park at Bartlett Playground.

(photos by Kate St. John)

Seen This Week

Orange jewelweed, Beechwood Nature Center, 16 August 2023 (photo by Kate St. John)

26 August 2023

Well, mostly “this week.” Two photos are older but I didn’t have room for them last time. Here’s a selection spanning 12 days.

  • Orange jewelweed (Impatiens capensis), above, does well at ASWP’s Beechwood Nature Center but is nearly extirpated from Schenley Park by deer overbrowse.
  • Tiny pink and white flowers of willow-herb (Epilobium sp) at West Penn Park on Polish Hill.
  • Sneezeweed at ASWP’s Beechwood Nature Center. They’ve cultivated many native flowers in the meadows.
  • Porcelain berry leaves have many shapes, even on the same plant. A photo of four shapes.
  • Great lobelia at ASWP’s Beechwood Nature Center.
  • Pink-orange sunrise on 24 August.
Willow-herb, West Penn Park, Polish Hill, 20 August 2023 (photo by Kate St. John)
Common sneezeweed (Helenium autumnale), Beechwood Nature Center, 24 August 2023 (photo by Kate St. John)
4 shapes of porcelain berry leaves, Nine Mile Run Trail, Lower Frick, 13 August 2023 (photo by Kate St. John)
Great lobelia, Beechwood Nature Center, 24 August 2023 (photo by Kate St. John)
Sunrise in Pittsburgh, 24 August 2023 (photo by Kate St. John)

(photos by Kate St. John)

Shades of Yellow and a Purple Host

Common sunflower closeup, 14 Aug 2023 (photo by Kate St. John)

20 August 2023

Someone in my neighborhood planted common sunflower (Helianthus annuus) on the strip of land between the sidewalk and the street. This month it droops over the sidewalk, so tall that I barely have to duck to take this closeup of yellow with a golden cast. Did you know this food plant is native to the Americas?

This woodland sunflower (Helianthus divaricatus), in a sunnier shade of yellow, was identified on the Botanical Society walk last Sunday at the Nine Mile Run Trail. The side of the flower is displayed because the bracts on the back and the bud are important. Click on the image to see a front view of the flower.

Woodland sunflower, Nine Mile Run Trail, 14 Aug 2023 (photo by Kate St. John)

This very yellow “pale jewelweed” (Impatiens pallida) is a rarity in Schenley Park. Deer have eaten all the other jewelweed yet this patch thrives. Why? The clue is in middle of this ugly photo.

Do you see the prickly branch of wineberry draped over the jewelweed plant? The entire patch is protected by this invasive thorny plant. The deer cannot approach. (Wineberry stems are circled in purple below.)

Wineberry (circled) drapes over yellow jewelweed in Schenley Park, protecting it from deer, Aug 2023 (photo by Kate St. John)

And a Purple Host:

I don’t remember the exact species of tick trefoil seen on the Botanical Society walk but a butterfly confirmed the plant is thriving.

Tick trefoil is the host plant for the silver spotted skipper. This one was sipping on an wet abandoned shirt nearby its host.

Silver spotted skipper sipping on a wet cloth, NMR Trail, 14 Aug 2023 (photo by Kate St. John)

(photos by Kate St. John)